Cast your mind back to when SIGHUP first started getting sent to processes on logout. Some programs had to start making an new API call to block SIGHUP killing them. nohup was invented. Some admins probably disabled SIGHUP for a while as it sorted out, and some probably called for these kids and their newfangled signals to get off their lawn. So it goes.

> Cast your mind back to when SIGHUP first started getting sent to processes on logout.

That would be before 1979. nohup was in 7th Edition. I haven't checked 6th.

Ironically, by pointing to the fact that one has to go back through 37 years of documentation, education, user experience, and scripts you are making other people's point for them. Especially by drawing attention to one of the major flaws in the "nohup was new once" argument, which is that in 1979 (or before) there wasn't a prior 37 years built up to contradict. (-:

justinsaccount

I was curious what the oldest reference of it was,

https://github.com/dspinellis/unix-history-repo.git

has different branches for various unix versions

Seems the earliest reference I could find in there was dated november 1973, but it is from a full import in 77:

commit c849507974bd2c0e2fd8c17e06f6f65b68075ca9 Author: Bill Joy Date: Wed Nov 23 12:43:50 1977 -0800

    Start development on BSD 1
    Create reference copy of all prior development files
    
    
    Synthesized-from: 1bsd

Some of the earlier copies i can see were even just shell scripts:

  trap "" 1 15
  if test -t 2>&1  ; then
	  echo "Sending output to 'nohup.out'"
	  exec nice -5 $* >>nohup.out 2>&1
  else
  	exec nice -5 $* 2>&1
  fi

Research-V3-Snapshot-Development did not have nohup Research-V4-Snapshot-Development had the nohup man page but not nohup Research-V5-Snapshot-Development has nohup.c

commit 0281f55d1cf7aa94555d8522d8b37161b97791be Author: Ken Thompson Date: Tue Nov 26 18:13:21 1974 -0500

    Research V5 development
    Work on file usr/source/s2/nohup.c
    
    Co-Authored-By: Dennis Ritchie 
    Synthesized-from: v5

Then later v7 reverted back to the shell version

commit 6144d5b3a973b515977eef01a828cdd82c480fe3 Author: Ken Thompson Date: Wed Jan 10 15:25:04 1979 -0500

    Research V7 development
    Work on file bin/nohup
    
    Co-Authored-By: Dennis Ritchie 
    Synthesized-from: v7